The population of the United States is aging and the number of elderly with age-related chronic disease, such as periodontal disease, is likely to increase as well. Prevention or delaying the onset of such diseases is one way to reduce the costs incurred by health care services for treatment of chronic disease of the elderly. Maintaining the integrity of the periodontium is of essential importance in older populations as proper dental health enables consumption of a nutritious diet, which in turn helps prevent development of other chronic diseases. Vitamin D deficiency and insufficiency is prevalent in the United States, and the elderly are at a particular increased risk of having low vitamin D status. As vitamin D has been shown to have both immune modulating and anti-microbial properties, in addition to its effects on bone mineral density, it could potentially protect against development and progression of periodontal disease. To date, limited data exists on the role of vitamin D status as a risk factor for periodontal disease, and no data has investigated the effect of vitamin D status, assessed with a blood biomarker, on progression of periodontal disease. The purpose of this proposal is to investigate associations between vitamin D status and periodontal disease in an aging cohort (aged 53-85 years) of postmenopausal women. We will use previously collected data and plasma from a prospective ancillary study on osteoporosis and periodontal disease conducted within the Buffalo clinic center of the Women's Health Initiative Observational Study (WHI OS). The baseline examination of this prospective ancillary study was conducted from 1997-2000 as an addition to the WHI OS 3 year clinic visit. The participants were then recruited again 5 years later for a follow-up exam from 2002-2005. Specifically, this proposal has two main aims: 1) To determine whether vitamin D status, assessed with plasma 25- hydroxyvitamin D (25(OH)D) concentrations, at baseline (1997-2000) is associated with prevalent periodontal disease assessed at baseline among 935 women with stored baseline plasma, and 2) To determine whether vitamin D status, assessed with plasma 25(OH)D concentrations, at baseline is associated with progressive of periodontal disease determined among 694 women attending the 5-year study follow-up (2002-2005) with stored baseline plasma. At both study visits a standardized oral examination was conducted, blood was drawn, and risk factor data specific to periodontal disease were collected. Additionally, at both visits, detailed data on diet, supplement and medication use, and other factors including lifestyle habits and medical history were collected. This dataset contains a uniquely detailed oral examination with information on alveolar crestal bone height (ACH), determined from intraoral radiographs, measures of probing depth (PD) and clinical attachment loss (CAL). This study will advance our understanding of vitamin D status in relation to periodontal disease prevalence and progression. If vitamin D status is determined to be a risk factor, this could potentially have a significant impact on the dental and overall health of aging populations. PUBLIC HEALTH RELEVANCE: Periodontal disease is highly prevalent in the US aging population. Maintaining adequate vitamin D status may have a significant impact on preventing or delaying progression of periodontal disease due to its proposed anti- inflammatory and anti-microbial properties. The main purpose of this study is to investigate associations between prevalent and progressive periodontal disease and vitamin D status in a longitudinal study of aging post-menopausal women.